The generally employed automobile suspension is comprised of a coil spring and a hydraulic damper. In the case of a suspension with such a structure, when the suspension receives an impact (shock), the coil spring is compressed, and thereby absorbs the mechanical energy. Thereafter, when the coil spring is extended, the absorbed energy is transferred to the hydraulic damper, and the hydraulic damper dissipates the energy of shock and vibration by converting the mechanical energy into thermal energy by virtue of the fluid friction.
As an example of previously developed damper, a colloidal damper which accommodates in a closed space a mixture of a porous body, such as silica gel, and a working liquid, and allows the working liquid to flow-into the pores of the porous body and to flow-out from the pores of the porous body in order to dissipate the mechanical energy externally applied to the colloidal damper has been developed (see for instance, the Patent References 1 and 2). Furthermore, the inventor of the present invention has made improvements of the colloidal damper, as shown in the Patent References 3 to 5, in order to be able to maintain the requisite performances, even the colloidal damper is repeatedly used over a sufficient number of cycles, according to a specific practical application.    Patent Reference 1: International Publication 96/18040 pamphlet    Patent Reference 2: International Publication 01/55616 pamphlet    Patent Reference 3: Japanese Patent Application Publication No. 2004-44732    Patent Reference 4: Japanese Patent Application Publication No. 2005-121092    Patent Reference 5: Japanese Patent Application Publication No. 2006-118571